GSK employees are accused of paying “large bribes” laundered through travel agencies to doctors, hospitals and others to “to open new sales channels and increase drug revenues,” said a Public Security Ministry announcement. It said the scheme “lasted a long time” but gave no details.

They also are suspected of tax offenses involving collusion with travel agencies to issue false invoices, the ministry said. It identified the employees only as “high officials” of Britain-based GSK and gave no details of the size of payments or who received them.

GSK said that it would cooperate with the authorities but said Thursday’s announcement was the first official communication it has received about the investigation.